This time, for the first time, the challenge comes from within. Teams take fliers on quarterbacks in the third and fourth rounds. Teams use first-round picks on players they view as potential franchise quarterbacks.

Flacco has responded like he has at the most critical points of his football career -- with a combination of quiet defiance and a bold display of confidence.

"He’s very secure with himself, more so than in the past," Ravens safety Eric Weddle said. "He believes in what he is and what he can do. Obviously, you draft a quarterback in the first round, and it’s got to be motivating to you. If not, you wouldn’t have played like that."

Weddle's comment came after Flacco threw three touchdowns in a season-opening 47-3 win over the Buffalo Bills. On Thursday night, a national television audience will tune in to see this resurgent Flacco take on the Cincinnati Bengals.

Teammates started talking in June about how the drafting of Jackson "lit a fire" in Flacco. He followed through with perhaps the best training camp of his 11-year career, and he finished as the NFL's highest-rated quarterback of the preseason.

When you bring up the narrative of the newly inspired Flacco, the one who refuses to buy into it is Flacco himself.

"I always tell people, ‘If you’re not motivated to play in this league from within, then you’re not going to make it very long,'" Flacco said. "Obviously, there are little things along the way that serve as motivation, maybe on one given day or the other. But even if I was motivated by that, it’s not something that would last. That’s not the kind of motivation that gets you through anything significant. I am who I am every single day, and I think we’ve been doing a good job this offseason, this training camp, and all the way into Week 1."

Different look, different attitude

Flacco has a different look about him, and it goes beyond the sleeker physique and the slight speckling of gray in his beard. When Flacco threw a bad pass in training camp, you could hear him slap his hands from the other end of the field. When he threw one of his few bad passes Sunday, his body slumped over with his hands on his knees.

He speaks with a different level of brashness, especially when his role or reputation is questioned.

Asked about Ramsey's remark, Flacco replied, "I don't really care. There's plenty of people out there saying things. Just add one more to the list. No big deal."

Asked if there is going to be a point in the season where he grows sick of the repeated questions about Jackson, Flacco said, "No, I don't, because I think we're going to win and we're not going to hear about it."

Pitta, one of Flacco's closest friends, believes the addition of Jackson has played a role in motivating Flacco.

"Anytime you draft a first-round player at your position, you see the writing on the wall and you understand what that means, especially at the quarterback position," Pitta said. "The team and the fans want to see what he’s capable of at the head of this offense and this team. It won’t be any different for Lamar Jackson and Joe Flacco. So, Joe has a big job ahead of him to hold off the fans and everybody else and to prove he’s still the quarterback here in Baltimore."

Something to prove

History shows Flacco is at his best when he has something to prove.

In college, Flacco transferred to Delaware after Pittsburgh chose Tyler Palko as its starting quarterback. Flacco went on to become a first-round pick.

Entering the 2012 season, Flacco decided to bet on himself when he felt the Ravens' contract offer was lacking. Flacco went on to become Super Bowl MVP and the NFL's highest-paid player.

This year, Flacco watched the Ravens take a quarterback in the first round for the first time since they drafted him in 2008. On Sunday, he went on to produce a passer rating of 121.7, the seventh-best of his career and his highest in four years.

Joe Linta, Flacco's agent, expects Flacco to have a bounce-back season. He doesn't believe it has anything to do with the arrival of Jackson.

Linta insists Flacco "doesn't care" about any offseason move because the quarterback's focus is on himself.

"It didn’t matter if they brought in Aaron Rodgers or this guy or the next guy," Linta said. "This is going to sound very cliche, but I’ve never met a guy in my life who’s like, ‘Whatever they do, they do. I’ve got to do my thing.’ He knows how good he is. He doesn’t need somebody to tell him that."

Feeling no pain

The Ravens see health as the bigger storyline with Flacco. In 2015, Flacco missed the last six games of the season after tearing the ACL and MCL in his left knee. In 2016, he sat out all of the spring offseason workouts while recovering from knee surgery. Last year, he was sidelined through all of training camp and the preseason with a back injury.

From 2015 to 2017, Flacco was the NFL's 33rd-ranked passer (82.4), throwing 52 touchdowns and 40 interceptions. Last season, he recorded a career-worst 5.7 yards per attempt.

In Sunday's opener, Flacco was decisive, accurate and mobile, rolling out of the pocket to elude pressure.

In comparing Flacco this year to 2017, Harbaugh said, "It’s night and day. Try to develop a passing offense without your quarterback all through training camp. Anybody who can’t recognize the difficulty of that doesn’t know football."

Flacco's future in Baltimore is uncertain. If he struggles, the Ravens can cut him at the end of the season, which would free up $10.5 million. If Flacco plays well, the Ravens could trade him like the Kansas City Chiefs did with Alex Smith a year after drafting Patrick Mahomes in the first round.

A large part of the franchise's decision will be based on the development of Jackson and the confidence of the team in him to take over as the starting quarterback. It's not out of the question for the Ravens to keep Flacco for the next two seasons if he continues to play at a high level.

Flacco immediately helped the Ravens become a perennial playoff team, guiding Baltimore to the postseason in his first five seasons, including three AFC Championship Games and one Super Bowl title. After a playoff drought, the pressure is on Flacco to cement his legacy.

"Over the last couple of seasons, people have really forgotten what Joe Flacco is capable of and the elite level he’s able to play at," Pitta said. "I think a big run this year, a postseason run, where he plays well, I think we’ll all be reminded of how important he has been to this franchise over the last decade and what he means to the city of Baltimore. I know he wants to finish his career as a Baltimore Raven. It means a lot to him. He’s loved playing in that city. He wants to do everything he can to at least leave on a good note and do all he can to help that city."